Factors influencing evaporation rate Steps:

• Evaporation rate depends on exposed surface area, water temperature, air movement over the surface, and humidity.
• Initially, water and room are at equilibrium temperature, so rate is set by surface conditions.
• Evaluate each change for impact on these factors at the start.
• Only changes to surface area or air flow alter the initial rate.

Why A is correct:

• Thicker glass does not change water surface area, initial temperature, or air flow, per basic evaporation principles (rate independent of container wall thickness without external heating).

Why the others are wrong:

• B: Larger cross-sectional area increases water surface area, raising total evaporation rate (proportional to area).
• C: Fan increases air speed, enhancing vapor removal and rate (via increased mass transfer coefficient).
• D: Identical to C, so also increases rate through better air circulation.

Final answer: A